Study On Hydrodynamic Performance Of Current Turbine Based On Overlap Grid Method

As a widely distributed,powerful and stable renewable energy source,marine current energy can provide long-term energy supply for marine equipment such as marine space station,preset weapons,charging base stations,and ocean submersible,therefore,how to develop and utilize the current power efficiently has become a hot issue in current research.As an efficient and stable device that can convert current power into electric energy,current turbine can be widely used in the utilization of current power.In the process of current turbine design,the complicated current environment has a great influence on the hydrodynamic performance of turbines,how to improve the efficiently of turbine in complicated current environment is the key direction of research.This paper first analyzes and studies the current environment around turbines,according to the characteristics of low velocity of the sea current around the turbine,and the operation of turbine is affected by the fluctuation of the flow velocity and direction,based on the momentum theory,blade element theory and the basic theory of the balde design,the design process of the turbine blade is studied in detail.According to the marine equipment energy supply needs and characteristics of the working enviroment,proposed turbine design technical indicators,and based on the design specifications,the design and modeling of turbine blades were comlpeted by using the Wilson design method.Based on the establishment of the turbine model,this paper mainly studies the hydrodynamic performance of turbines under complicated current environment from the perspective of CFD simulation.In order to simulate the complex movement of turbine,the overlap grid technique and the DFBI motion solution model be used to monitor in detail the flow filed changes and hydrodynamic performance of turbine under unsteady incoming flow.In order to study the hydrodynamic performance of turbines under complicated current environment,the main variables of flow rate and direction are taken an the research variables,by changing the inlet conditions of the flow field to simulate the unsteady flow conditions,the influence of different flow velocity and direction on the hydrodynamic performance of turbines.Studies have shown that unsteady flow and flow fluctuations can cause fluctuations in the flow field around the turbine,blade stalls lead to a rapid drop in turbine energy efficiency.As a result,turbines is affected by unsteady flow.In view of flow rate and unsteady flow on the hydrodynamic performance of turbine,this paper presents a structural optimization design of the turbine uesing the dome and tail radder.The research shows that the installation of the dom can restrain the influence of the flow velocity fluctuation on the hydrodynamic performance of the turbine,and effectively improve the energy effciency of turbine.The installation of the tail radder structure can realize the self-convection operation of the turbine,and weaken the influence of the change of the flow direction on the energy effciency of turbine.The research results of this paper can provide reference and guidance of the design and application of current turbine,it has important theoretical significance and application value.